The prior art electrostatic chuck is described in U.S. Pat. No. 4,184,188, issued Jan. 15, 1980. Related patents included U.S. Pat. Nos. 4,949,783, issued Aug. 21, 1990 and 4,864,461, issued Sep. 5, 1989. A related publication is Wardly Electrostatic Wafer Chuck for Electron Beam Microfabrication, 1506 Rev. Sci. Instrum., Vol. 44, No. IV, October 1973.
The prior art electrostatic chuck includes a water cooled bottom plate, an electrostatic plate supported by the water cooled bottom plate, and a printed circuit capacitor supported by the electrostatic plate and two sets of electrodes disposed on the electrostatic plate and two sets of electrodes disposed on the bottom silicone layer and a top silicone layer disposed on the two sets of electrodes, whereby an electrostatic field can be formed for clamping a substrate to the electrostatic plate and whereby heat is conducted from the wafer to the water cooled plate.
One problem with the prior art electrostatic chuck is that the operating voltage for forming a suitable chuck electrostatic field is relatively high.